CN104093381A - Catheter having hydraulic actuator with tandem chambers - Google Patents

Abstract

Catheter including an inner tubular member having a fluid lumen defined therein and an exterior surface. The exterior surface defining a first distal flow port and a second distal flow port. An outer tubular member is movable relative to the inner tubular member in a proximal direction and having an interior surface. A first pressure chamber is defined between the exterior surface and the interior surface, and between a first distal seal assembly and a first proximal seal assembly. A second pressure chamber is defined between the exterior surface and the interior surface, and between a second distal seal assembly and a second proximal seal assembly. Fluid introduced through the fluid lumen pressurizes the first pressure chamber and the second pressure chamber to generate a respective force at the first proximal seal assembly and to the second proximal seal assembly to urge the outer tubular member in the proximal direction.

Description

Conduit with hydraulic actuator with chambers in series

Cross References to Related Applications

This application claims the benefit of, claims priority to, and claims priority to US Application Serial No. 13/467,715, filed May 9, 2012, which is hereby incorporated by reference in its entirety.

technical field

The disclosed subject matter relates to catheters used in the delivery of medical devices, such as self-expanding stents for treating a luminal system of a patient. In particular, the disclosed subject matter relates to a delivery catheter having a retractable sheath moved by a hydraulic chamber.

Background technique

In the context of intraluminal delivery of medical devices such as stents or filters, various systems using retractable sheaths are known. However, there remains a continuing need for improvements to such known delivery systems.

An example of such a delivery system is described in US Patent No. 6,425,898 to Wilson et al., which is incorporated herein by reference, wherein the delivery system is provided with an internal component with a stopper attached thereto. During deployment, the stop prevents proximal movement of the stent during retraction of the sheath for deployment of the stent.

Conventional self-expanding stent delivery systems generally include a handle portion and an elongated shaft, wherein the stent is disposed within the delivery portion at the distal end of the shaft. To deploy the stent, an outer sheath is provided that is retractable relative to the stent to release the stent from its delivery configuration. The sheath in such systems typically spans the full length of the catheter, resulting in increased profile and stiffness throughout the entire length of the catheter. Also, because the sheath spans the full length of the catheter, there is an increased risk that the sheath will bind with other components of the catheter during passage through the patient's tortuous luminal system, thereby hindering stent deployment.

Another problem with such delivery systems is that user input (force) is typically utilized to pull the sheath back at a 1 to 1 ratio. Because the stent can become embedded in the sheath during storage and shipping, and due to the greater stiction, a substantial initial input is usually required to release the stent, which can lead to incorrect placement. When initially releasing the stent, it may be desirable to pull the sheath back slowly for proper placement, and then retract the sheath more easily to prevent inadvertent movement of the stent.

Also, the amount of force required to retract the sheath (in particular, for a stent of greater length as the periphery dictates requires) can be substantial. Accordingly, there is a need for an improved delivery system for self-expanding stents with reduced force requirements for delivering the medical device.

Thus there remains a continuing need for an efficient and economical system for delivering medical devices that is easy to use and provides accurate stent placement. The presently disclosed subject matter satisfies these and other needs.

Summary of disclosed subject matter

Objects and advantages of the disclosed subject matter will be set forth in and will be apparent from the description that follows, and will also be learned by practice of the disclosed subject matter. Further advantages of the disclosed subject matter will be realized and attained not only by the means particularly pointed out in the written description and claims hereof, but also from the accompanying drawings.

When using a hydraulic system to deploy a stent, the resultant force applied to retract the outer tubular member is generally a function of pressure and area. However, the outer tubular member of the hydraulic cylinder may initially require a larger retraction force to retract. Thus, in some circumstances it may not be desirable to sustain a high retraction force throughout the entire travel or movement of the outer tubular member. Accordingly, tandem chamber catheters are disclosed herein to allow redistribution of retraction forces, enabling the generation of initially higher retraction forces followed by lower retraction forces during deployment.

To achieve these and other advantages, and in accordance with the purposes of the disclosed subject matter, as embodied and broadly described, the disclosed subject matter includes a catheter comprising an inner tubular member having a length, an outer surface, and A fluid lumen defined therein. The outer surface defines a first distal flow port in fluid communication with the fluid lumen and a second distal flow port in fluid communication with the fluid lumen positioned proximally relative to the first distal flow port. The catheter also includes an outer tubular member movable in a proximal direction along the length of the inner tubular member relative to the inner tubular member. The outer tubular member has an inner surface facing the outer surface of the inner tubular member.

A first pressure chamber is defined between the outer surface of the inner tubular member and the inner surface of the outer tubular member, and between the first distal seal assembly and the first proximal seal assembly. The first pressure chamber is in fluid communication with the first distal flow port. A second pressure chamber is defined between the outer surface of the inner tubular member and the inner surface of the outer tubular member, and between the second distal seal assembly and the second proximal seal assembly. The second pressure chamber is configured proximally relative to the first pressure chamber and is in fluid communication with the second distal flow port. Fluid introduced through the fluid lumen pressurizes the first and second pressure chambers to generate corresponding forces at and against the first proximal seal assembly to drive the outer tubular part.

According to another aspect of the disclosed subject matter, there is provided a method of delivering a device comprising providing a catheter comprising an inner tubular member having a length, an outer surface, and a fluid lumen defined therein. The outer surface defines a first distal flow port in fluid communication with the fluid lumen and a second distal flow port in fluid communication with the fluid lumen positioned proximally relative to the first distal flow port. The catheter also includes an outer tubular member movable in a proximal direction along the length of the inner tubular member relative to the inner tubular member. The outer tubular member has an inner surface facing the outer surface of the inner tubular member.

A first pressure chamber is defined between the outer surface of the inner tubular member and the inner surface of the outer tubular member, and between the first distal seal assembly and the first proximal seal assembly. The first pressure chamber is in fluid communication with the first distal flow port. A second pressure chamber is defined between the outer surface of the inner tubular member and the inner surface of the outer tubular member, and between the second distal seal assembly and the second proximal seal assembly. The second pressure chamber is configured proximally relative to the first pressure chamber and is in fluid communication with the second distal flow port. Fluid introduced through the fluid lumen pressurizes the first and second pressure chambers to generate corresponding forces at and against the first proximal seal assembly to drive the outer tubular part.

The method also includes disposing the device between the outer surface of the inner tubular member and the inner surface of the outer tubular member in a distal position relative to the first distal seal assembly. The method also includes introducing fluid into the fluid lumen to pressurize the first pressure chamber and the second pressure chamber to generate corresponding forces at the first proximal seal assembly and the second proximal seal assembly to move along the proximal The outer tubular member is moved sideways to expose the device.

It is to be understood that both the foregoing general description and the following detailed description and accompanying drawings are examples and are provided for purposes of illustration and are not intended to limit the scope of the disclosed subject matter in any way.

The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to illustrate and provide a further understanding of the device of the disclosed subject matter. Together with the description, the drawings serve to explain the principles of the disclosed subject matter.

Description of drawings

The subject matter of the present application will be more readily understood from the following Detailed Description when read in conjunction with the accompanying drawings, in which:

Figure 1 is a schematic side view of a representative catheter according to the disclosed subject matter;

1A is a cross-sectional view taken along line A-A of FIG. 1 depicting an embodiment of an inner tubular member in a coaxial configuration, according to an embodiment of the disclosed subject matter;

1B is an enlarged detailed cross-sectional side view of the first pressure chamber of the catheter of FIG. 1 , wherein the guidewire lumen has an over-the-wire configuration;

1C is an enlarged detailed cross-sectional side view of the first pressure chamber of the catheter of FIG. 1 , wherein the guidewire lumen has a rapid exchange configuration;

2A is a cross-sectional perspective view of an embodiment of an inner tubular member depicting a monolithic multi-lumen configuration, taken along line A-A of FIG. 1 , according to an embodiment of the disclosed subject matter;

Figure 3 is a perspective view of the distal section of the catheter of Figure 1;

4A-4D are schematic side sections depicting representative embodiments of catheters of the disclosed subject matter having a first pressure chamber and a second pressure chamber with an initial expansion space therebetween;

Figure 5 is a schematic side section of the distal end of a catheter of the disclosed subject matter having three pressure chambers with an initial inflation space between them;

6A-C are schematic side sections of an embodiment of a one-way distal stopper configuration between adjacent pressure chambers during deployment;

7 is a schematic diagram of force and distance according to an embodiment of the disclosed subject matter.

Detailed ways

Reference will now be made in detail to embodiments of the disclosed subject matter, examples of which are illustrated in the accompanying drawings. The disclosed subject matter will be described in conjunction with a detailed description of the system.

In accordance with the disclosed subject matter, there is provided a catheter comprising an inner tubular member having a length, an outer surface, and a fluid lumen defined therein. The outer surface defines a first distal flow port in fluid communication with the fluid lumen and a second distal flow port in fluid communication with the fluid lumen positioned proximally relative to the first distal flow port. The catheter also includes an outer tubular member movable in a proximal direction along the length of the inner tubular member relative to the inner tubular member. The outer tubular member has an inner surface facing the outer surface of the inner tubular member.

A first pressure chamber is defined between the outer surface of the inner tubular member and the inner surface of the outer tubular member, and between the first distal seal assembly and the first proximal seal assembly. The first pressure chamber is in fluid communication with the first distal flow port. A second pressure chamber is defined between the outer surface of the inner tubular member and the inner surface of the outer tubular member, and between the second distal seal assembly and the second proximal seal assembly. The second pressure chamber is configured proximally relative to the first pressure chamber and is in fluid communication with the second distal flow port. Fluid introduced through the fluid lumen pressurizes the first and second pressure chambers to generate corresponding forces at and against the first proximal seal assembly to drive the outer tubular part.

According to another aspect of the disclosed subject matter, there is provided a method of delivering a device comprising providing a catheter comprising an inner tubular member having a length, an outer surface, and a fluid lumen defined therein. The outer surface defines a first distal flow port in fluid communication with the fluid lumen and a second distal flow port in fluid communication with the fluid lumen positioned proximally relative to the first distal flow port. The catheter also includes an outer tubular member movable in a proximal direction along the length of the inner tubular member relative to the inner tubular member. The outer tubular member has an inner surface facing the outer surface of the inner tubular member.

A first pressure chamber is defined between the outer surface of the inner tubular member and the inner surface of the outer tubular member, and between the first distal seal assembly and the first proximal seal assembly. The first pressure chamber is in fluid communication with the first distal flow port. A second pressure chamber is defined between the outer surface of the inner tubular member and the inner surface of the outer tubular member, and between the second distal seal assembly and the second proximal seal assembly. The second pressure chamber is configured proximally relative to the first pressure chamber and is in fluid communication with the second distal flow port. Fluid introduced through the fluid lumen pressurizes the first and second pressure chambers to generate corresponding forces at and against the first proximal seal assembly to drive the outer tubular part.

The method also includes disposing the device between the outer surface of the inner tubular member and the inner surface of the outer tubular member at a position distal relative to the first distal seal assembly. The method also includes introducing fluid into the fluid lumen to pressurize the first and second pressure chambers to generate corresponding forces at the first and second proximal seal assemblies to move along the proximal The outer tubular member is moved sideways to expose the device.

The catheters and methods disclosed herein can be used in various treatments of a patient's luminal system. For example, the disclosed subject matter is particularly suited for use in the treatment of a patient's cardiovascular system, such as the delivery of a medical device into the vasculature.

Reference will now be made in detail to specific embodiments, examples of which are illustrated in the accompanying drawings, for purposes of illustration only. The examples are not intended to limit the scope of the disclosed subject matter in any way. For the purposes of this disclosure, like reference numbers in the figures shall refer to like features unless otherwise indicated. While specific reference is made to various embodiments of catheters and methods for delivering stents, the catheters and methods can likewise be modified for use and delivery of other devices and for use and delivery in other intraluminal systems.

For purposes of illustration only, embodiments of hydraulic delivery systems, at least a portion of which deliver within the vasculature or other body lumen, are schematically shown in the drawings. 1 , 1B and 1C illustrate cross-sections of an example catheter 100 . As discussed further below, catheter 100 generally includes an inner tubular member 110 having a length and an outer surface, wherein the inner tubular member defines at least a fluid lumen therein. A guidewire receiving lumen may also be provided along at least a portion of the length of the shaft. A guidewire can be inserted into the guidewire lumen.

Inner tubular member 110 may comprise a variety of suitable configurations. For purposes of illustration only, Figure IB illustrates an over-the-wire (OTW) configuration. In this embodiment, the inner tubular member includes a guidewire lumen 140 that extends generally along the entire length of the inner tubular member. In this embodiment, only the first pressure chamber C1 is depicted in FIG. 1B for the sake of clarity. The structure and operation of the pressure chamber C1 will be explained in more detail below. Additional pressure chambers may be provided, as further described in accordance with the disclosed subject matter.

Figure 1C illustrates a rapid exchange configuration (RX), with only the first pressure chamber C1 depicted for clarity. In this embodiment, guidewire lumen 140 extends from proximal guidewire port 147 to the distal end of inner tubular member 110 .

In OTW or RX configurations, the inner tubular member may also have a coaxial arrangement or a multi-lumen arrangement. For example, FIG. 1A depicts a representative cross-sectional view of a coaxial arrangement along line A-A of FIG. 1 . The coaxial arrangement includes an inner tubular member 110 having a wire guide tube 141 disposed therein. In this embodiment, a fluid lumen 130 is defined between the inner tubular member 110 and the guidewire tube 141 . Guidewire tube 141 also defines guidewire lumen 140 as discussed further below. In this embodiment, the inner tubular member may be a single tube or an assembly of members coupled together.

The coaxial inner tubular member 110 is also shown schematically in FIGS. 1B and 1C for purposes of discussion and reference. Inner tubular member 110 has a proximal portion, a distal portion and a length. As depicted in FIGS. 1B and 1C , the inner tubular member 110 includes a guidewire lumen 140 and a fluid lumen 130 therein defined at least along the length of the inner tubular member 110 .

As discussed further herein, the guidewire lumen 140 may thus be at least partially defined by a separate guidewire tube 141 disposed within the fluid lumen 130 of the inner tubular member 110 and sealed at either end. Guidewire lumen 140 may receive a guidewire therein. In an OTW catheter such as the catheter of FIG. 1B , guidewire lumen 140 extends along the length of catheter 100 . In contrast, in an RX catheter such as the catheter of FIG. 1C , the guidewire lumen 140 extends along the distal end along a portion of the length of the catheter. For example, depending on whether the catheter is an OTW catheter or an RX catheter, guidewire lumen 140 includes a proximal guidewire port 147 at the proximal end of the guidewire lumen. The guidewire lumen has a distal guidewire port 430 at the distal end of the catheter 100 . For example, and as embodied herein, as shown in FIG. 1 , catheter 100 has a distal tip 460 at the distal end to define distal guidewire port 430 . As described further below and depicted in FIG. 1B , the distal tip 460 may also define a distal end for a stent mount 3 or the like.

Alternatively, and for purposes of illustration only, Figure 2A depicts a representative cross-sectional view of a multi-lumen arrangement. For example, without limitation, the inner tubular member 110 may be a unitary member having a multi-lumen configuration. In such an embodiment, the inner tubular member 110 defines both a guidewire lumen 140 and a fluid lumen 130 therein.

In either embodiment, fluid lumen 130 defines a pathway for fluid to be introduced from the proximal end of catheter 100 to the distal end of the inner tubular member. An adapter may be provided at the proximal end of the catheter for access to the fluid lumen and may be configured to connect to a fluid source (not shown). Accordingly, fluid may communicate between the adapter and the distal flow port at the distal end of the inner tubular member via fluid lumen 130, as discussed further herein.

Fluid can be introduced into the fluid lumen by conventional means such as, but not limited to, an inflator or syringe. A pressurizer may be provided to control the inflation and deflation of the pressure chamber and expansion space. The pressurizer may also include a threaded engagement or locking mechanism to control the pressurization and depressurization of the pressure chamber (not shown). Additionally, the pressure gauge may have a pressurizer to monitor the pressure system of the catheter. The pressurizer may also be configured to allow a quick release of hydraulic pressure to stop or hinder deployment of the stent. The pressurizer may also be configured to create and/or maintain negative pressure in the catheter. The pressurizer may have a locking mechanism to maintain negative pressure in the catheter. The pressurizer can also create a vacuum that reduces the profile of the catheter. For example, by creating a vacuum, the outer tubular members disclosed herein can be configured to reduce profile and/or lock in place. An example of a suitable pressurizer is the Atrion pressurizer Atrion Medical-55ATM.

In an alternative embodiment, the fluid lumen and guidewire lumen are formed as a single shared lumen. Thus for such a coaxial arrangement, fluid can flow within the shared lumen, and a guidewire can be inserted into the shared lumen. In such a configuration, the inner tubular member may include proximal and distal guidewire seals disposed in a shared lumen to sealingly engage a guidewire disposed within the fluid lumen. Alternatively, the guidewire lumen can be formed from a membrane of suitable strength to resist penetration of the guidewire there, and be disposed within and along the length of the fluid lumen in a coaxial configuration. As discussed further herein, schematic depictions of shared lumen configurations (seals not shown for clarity) and/or coaxial component configurations (membranes omitted for clarity) are provided in FIGS. 4A-D . Although omitted for clarity in FIGS. 4A-D for purposes of demonstrating fluid flow within the chamber, it should be appreciated that stopper 31 includes a guidewire lumen extending therethrough. This shared or membrane-coaxial configuration allows for a reduced diameter of the inner tubular member and, thus, a reduced cross-section of the catheter.

Referring to FIG. 1B , outer surface 111 defines a first distal flow port 421 along a distal portion of inner tubular member 110 in fluid communication with fluid lumen 130 . Fluid can travel through fluid lumen 130 and exit fluid lumen 130 at first distal flow port 421 . As further disclosed herein, outer surface 111 may define a plurality of flow ports. As depicted in FIGS. 4A and 5 , a second distal flow port 422 is defined by the outer surface 111 along the distal portion of the inner tubular member 110 , wherein the second distal flow port 422 is also connected to the fluid lumen 130 fluid communication. The second distal flow port 422 is configured proximally relative to the first distal flow port 421 . As provided in FIG. 5 , a third or additional distal flow port 423 configured proximally relative to the second distal flow port 422 may also be provided if necessary or desired.

Each flow port defines an entry point for fluid communication between fluid lumen 130 and the environment surrounding outer surface 111 . If desired, each flow port may have two or more locations to exit to the surrounding environment, as depicted in FIG. 1B . Alternatively, as depicted in Figure 1C, each flow port may have only one exit to ambient. According to alternative embodiments, separate fluid lumens may be provided for each distal flow port.

As depicted in FIGS. 1 , 1B and 1C , catheter 100 also includes an outer tubular member or sheath 120 . As shown in FIGS. 1B and 1C , outer tubular member 120 has a proximal end, a distal end, a length, and an inner surface 121 . Inner tubular member 110 is positioned within outer tubular member 120 at least at the distal end of catheter 100 . Thus, the outer surface 111 of the inner tubular member 110 faces the inner surface 121 of the outer tubular member 120 such that the inner tubular member 110 is positioned within the outer tubular member 120 . The outer tubular member 120 is movable relative to the inner tubular member 110 along the length of the inner tubular member 110 . The outer tubular member 120 can be retracted in a direction P towards the proximal end of the catheter. As shown in Figures 1 and 3, the outer tubular member 120 may be deployed only at the distal portion of the catheter, if desired, to reduce the profile and increase the flexibility of the proximal section of the catheter. As further described herein, catheters of the disclosed subject matter may be configured to deliver medical devices, such as stents 2, of any suitable length. That is, the catheter may be configured to generate a force sufficient to retract the outer tubular member, wherein the generated force is greater than the resistance exerted on the outer tubular member by the medical device.

Moreover, in accordance with the disclosed subject matter, and as shown in FIG. 5 , as further described hereinafter, the conduit includes a first pressure chamber C1 defined between the outer surface 111 of the inner tubular member 110 and The inner surface 121 of the outer tubular member 120 is defined between the first distal seal assembly 160 and the first proximal seal assembly 150 . Additionally, and as further described, one or more additional chambers are provided proximally relative to the first pressure chamber. 4A depicts a schematic cross-sectional view of a representative embodiment of a catheter having a first pressure chamber Cl. Catheter 100 includes a first pressure chamber C1 in fluid communication with first distal flow port 421 . The first pressure chamber C1 assists in retracting the sheath 120 in the proximal direction P. As best seen in FIG. 5 , the first pressure chamber C1 is a substantially sealed chamber defined between the outer surface 111 of the inner tubular member 110 and the inner surface 121 of the outer tubular member 120 . Additionally, first proximal seal assembly 150 and first distal seal assembly 160 define proximal and distal ends, respectively, of first pressure chamber C1. The first pressure chamber C1 receives fluid from the fluid lumen 130 via the first distal flow port 421 . The pressure chamber C1 has an initial volume.

As depicted in FIG. 5 , first distal seal assembly 160 is distal relative to first distal flow port 421 and includes first distal seal 162 and first distal stop 161 . The first distal seal 162 is configured proximally relative to the first distal stop 161 . The first distal stop 161 extends from the outer surface 111 of the inner tubular member to the inner surface 121 of the outer tubular member. The first distal stop 161 blocks movement of the first distal seal 162 in the distal direction (which is opposite to the proximal direction P). For purposes of illustration only, first distal seal assembly 160 may also include a first distal bushing 163 as shown in the embodiment of FIG. 5 . The first distal bushing 163 provides a backing or similar structure for the first distal seal 162 and is disposed between the first distal stop 161 and the first distal seal 162 . The first distal bushing 163 is not attached to the outer tubular member 120 so as to allow the outer tubular member 120 to retract or otherwise slide freely across the first distal bushing 163 . Alternatively, the first distal seal assembly 160 may be a single or unitary element extending from the outer surface 111 of the inner tubular member 110 and sealingly engaging the inner surface 121 of the outer tubular member. In other embodiments, the first distal seal assembly 160 may include a plurality of elements extending from the outer surface 111 of the inner tubular member.

The first pressure chamber C1 also includes a first proximal seal assembly 150 . As further embodied herein, the first proximal seal assembly 150 is configured proximally relative to the first distal flow port 421 and includes a first proximal seal 152 and a first proximal stop 151 . The first proximal seal 152 is configured distally with respect to the first proximal stop 151 . A first proximal stop 151 extends from the inner surface 121 of the outer tubular member. As shown in the embodiment of FIG. 5 , first proximal seal assembly 150 may also include a first proximal bushing 153 as shown for illustration purposes only. The first proximal bushing 153 provides a backing for the first proximal seal 152 and is disposed between and proximal to the first proximal stop 151 relative to the first proximal seal 152 . Alternatively, first proximal seal assembly 150 may be a single or unitary element extending from inner surface 121 of outer tubular member 120 and sealingly engaging outer surface 111 of inner tubular member 110 . In other embodiments, first proximal seal assembly 150 may include multiple elements. As embodied herein, one or both of the proximal and distal seals may form a wiper seal across the corresponding surfaces, as is known.

As best seen in FIG. 4A , catheter 100 also includes a second pressure chamber C2 proximally relative to first pressure chamber C1 . The second pressure chamber C2 generally operates in series with the first pressure chamber C1 and operates in a similar manner to the first pressure chamber C1 . The first pressure chamber C1 and the second pressure chamber C2 may collectively generate an initial retraction force to initially drive the outer tubular member 120 in the proximal direction P. As shown in FIG. 4A depicts a schematic cross-sectional view of a second pressure chamber at the distal section of catheter 100 of FIG. 1 .

The second pressure chamber C2 is in fluid communication with the second distal flow port 422 . As best seen in FIG. 5 , the pressure chamber C2 is a substantially sealed chamber defined between the outer surface 111 of the inner tubular member 110 and the inner surface 121 of the outer tubular member 120 . A second proximal seal assembly 250 and a second distal seal assembly 260 are provided to define proximal and distal ends of the second pressure chamber. The second pressure chamber C2 receives fluid from the fluid lumen 130 via the second distal flow port 422 . The second pressure chamber C2 has an initial volume.

Second distal seal assembly 260 is distal relative to second distal flow port 422 and includes second distal seal 262 and second distal stop 261 . The second distal seal 262 is configured proximally relative to the second distal stop 261 . The second distal stop 261 extends from the outer surface 111 of the inner tubular member to the inner surface 121 of the outer tubular member. The second distal seal assembly 260 is free to move in the proximal direction P, but is hindered from moving in the distal direction (which is opposite to the proximal direction P) by the second distal stop 261 . Additionally, and as embodied herein, the second distal stop 261 may include a platform, step, rise, taper, coupled to or formed on the outer surface 111 of the inner tubular member. Bumps, wedges, one-way deflectors, etc.

For example, and with reference to the embodiment of FIGS. 4A and 5 , the second distal stop 261 may be formed by a sleeve or the like on the outer surface 111 of the inner tubular member. In this way, the sleeve forms a portion of the outer surface over which the first proximal seal 152 can travel during retraction of the outer tubular member. The proximal end of the sleeve defines a second distal stop in the form of a stopper to resist movement of the second distal seal 262 in the distal direction but to allow movement of the second distal seal in the proximal direction P. Likewise, the first proximal seal 150 can travel or move proximally across the step defined by the proximal end of the sleeve without hindrance. The first proximal seal 150 may be configured to maintain a seal between the outer surface 111 of the inner tubular member 110 and the inner surface 121 of the outer tubular member 120 even after being moved proximally relative to the proximal end of the sleeve. Alternatively, the first proximal seal 150 may be configured to allow leakage across it when proximal relative to the proximal end of the sleeve.

Figures 6A-6C illustrate an alternative embodiment in which a one-way stop is defined wherein the second distal stop 261 comprises a bump having, for example but not limited to, a cone or wedge shape shape. In this embodiment, a protrusion 261 is coupled to or formed on the outer surface 111 of the inner tubular member and is configured distally relative to the second distal component 260 . Protrusion 261 provides a one-way stop to prevent second distal assembly 260 from moving in a distal direction (which is opposite to proximal direction P) while still allowing first proximal seal assembly 150 to move in proximal direction P. The narrowest end of the bump 261 faces distally to form a ramp-like structure for the first proximal seal assembly 150 to travel up and over the bump in the proximal direction. The bump is sized such that the distal chamber proximal seal assembly 150 can slide proximally across the bump while preventing the proximal chamber second distal seal assembly 260 from moving distally. In this manner, first proximal seal assembly 150 can maintain a seal between the outer surface of inner tubular member and the inner surface of outer tubular member 120 even after traveling across and moving proximally relative to protrusion 261 . seal.

As best seen in FIG. 5 , second distal seal assembly 260 may also include a second distal bushing 263 . Second distal bushing 263 provides a backing for second distal seal 262 and is disposed between second distal stop 261 and second distal seal 262 . The second distal bushing 263 slides freely with the outer tubular member. Alternatively, the second distal seal assembly 260 may be a single or unitary element extending from the outer surface 111 of the inner tubular member 110 and sealingly engaging the inner surface 121 of the outer tubular member. In other embodiments, the second distal seal assembly 260 may include a plurality of elements extending from the outer surface 111 of the inner tubular member.

Second proximal seal assembly 250 is configured proximally relative to second distal flow port 422 and includes second proximal seal 252 and second proximal stop 251 . The second proximal seal 252 is configured distally with respect to the second proximal stop 251 . The second proximal stop 251 extends from the inner surface 121 of the outer tubular member 120 to the outer surface 111 . As depicted in the embodiment of FIG. 5 , the second proximal seal assembly 250 may also include, without limitation, a second proximal bushing 253 as shown for purposes of illustration. Second proximal bushing 253 provides a backing for second proximal seal 252 and is configured proximally relative to second proximal seal 252 .

According to another aspect of the disclosed subject matter, a first expansion space X1 is defined between the outer surface 111 of the inner tubular member and the inner surface 121 of the outer tubular member, and is located between the first pressure chamber C1 and the second pressure chamber C2 between. The first expansion space X1 may be initially vacuum-sealed and/or may be filled with a compressible fluid, such as CO2, an inert gas, a biocompatible gas, or the like. The first expansion space X1 allows the first pressure chamber C1 to expand toward the second pressure chamber C2.

For example, and with reference to the embodiment of FIGS. 4A-C , pressurized fluid introduced into fluid lumen 130 will enter first pressure chamber C1 via first distal flow port 421 and, into second distal flow port 422 . For purposes of clarity, the guide wire and guide wire lumen are not depicted. As shown in FIG. 4B , the first and second distal seal assemblies remain stationary relative to the inner tubular member 110 . However, the first proximal seal assembly 150 will be driven proximally by the pressure within the first pressure chamber C1 and, thereby, travel toward the second distal seal assembly 260 . As the first proximal seal assembly 150 is advanced proximally, the first pressure chamber C1 will increase in volume and the first expansion space X1 will decrease in volume. This travel will continue until the first proximal seal assembly 150 contacts the second distal seal assembly 260 or at least a portion thereof as shown in FIG. 4B . With continued pressurization of the first pressure chamber C1, the first proximal seal assembly 150 will drive the second distal seal 262 and second distal bushing 263 (if provided) in the proximal direction P until The configuration shown is proximal relative to the second distal flow port 422 .

Catheter 100 may also optionally include additional pressure chambers and expansion spaces at least initially disposed between adjacent pressure chambers. For example, FIG. 5 shows a third pressure chamber C3 provided proximally with respect to the second pressure chamber C2. As discussed herein, the third pressure chamber C3 works in series with the first pressure chamber C1 and the second pressure chamber C2, and generally operates in a similar manner to the pressure chambers.

For purposes of illustration only, FIG. 5 depicts a third pressure chamber C3 in fluid communication with a third distal flow port 423 . The third pressure chamber C3 receives fluid from the fluid lumen 130 via the third distal flow port 423 . The pressure chamber C3 is a substantially sealed chamber defined by the outer surface 111 of the inner tubular member 110 and the inner surface 121 of the outer tubular member 120 . A third proximal seal assembly 350 and a third distal seal assembly 360 are provided to define proximal and distal ends of the third pressure chamber C3. The pressure chamber C3 has an initial volume.

The third distal seal assembly 360 is distal relative to the third distal flow port 423 and includes a third distal seal 362 and a third distal stop 361 . The third distal seal 362 is configured proximally relative to the third distal stop 361 . The third distal stop 361 extends from the outer surface 111 of the inner tubular member to the inner surface 121 of the outer tubular member. The third distal seal 362 is configured proximally relative to the third distal stop 361 . The third distal seal assembly 360 is free to move in the proximal direction P, but is hindered from moving in the distal direction (opposite the proximal direction) by a third distal stop 361 . Additionally, and as embodied herein, the third distal stop 361 may include a platform, step, riser, coupled to or formed on the outer surface 111 of the inner tubular member, as previously described. Heights, sleeves, cylindrical bumps, wedges, one-way deflectors, etc.

For example, and with reference to the embodiment of Fig. 5, as similarly described above, the third distal stop 361 may be formed by a sleeve or the like on the outer surface of the inner tubular member.

In the embodiment of FIG. 5 , third distal seal assembly 360 may also include a third distal bushing 363 , as shown for illustration and without limitation. The third distal bushing 363 provides a backing for the third distal seal 362 and is disposed between the third distal stop 361 and the third distal seal 362 . The third distal bushing 363 is free to slide in the proximal direction P. Alternatively, third distal seal assembly 360 may be a single or unitary element extending from outer surface 111 of inner tubular member 110 and sealingly engaging outer tubular member inner surface 121 . In other embodiments, the third distal seal assembly 360 may include a plurality of elements extending from the outer surface 111 of the inner tubular member.

The third proximal seal assembly 350 is configured proximally relative to the third distal flow port 423 and includes a third proximal seal 352 and a third proximal stop 351 . The third proximal seal 352 is configured such that the third proximal stop 351 is distal. A third proximal stop 351 extends from the inner surface 121 of the outer tubular member. Third proximal seal assembly 350 may also include a third proximal bushing 353 . The third proximal bushing 353 provides a backing for the third proximal seal 352 and is disposed between and proximal to the third proximal stop 351 relative to the third proximal seal 352 .

Referring to the embodiment of FIG. 5, the second expansion space X2 may be provided between the second pressure chamber C2 and the third pressure chamber C3. As described above with reference to FIGS. 4A-4C , the second expansion space X2 is configured and operates in a manner similar to that of the first expansion space X1 .

Since relatively high fluid pressures are required to drive retraction of the outer tubular member 120, the pressure chamber is formed to withstand the operating pressure with minimal or no leakage. Various suitable seal configurations and materials may be used, such as, but not limited to, slide seals, rings, cup seals, lip seals, and compression bushings. In one embodiment, catheter 100 also includes bellows or bladder members within each pressure chamber to prevent leakage. Bellows or bladder members are coupled to the outer surface of inner tubular member 110 and are in fluid communication with flow ports 421 , 422 and 423 , wherein fluid introduced through the flow ports expands the members to assist in retracting the outer tubular member.

Embodiments of the disclosed subject matter provide pressure chambers capable of handling a wide range of suitable pressures. For purposes of illustration only, in one embodiment, the pressure chamber is operable up to a positive pressure of 750 psi and a negative pressure of approximately 14 psi.

According to another aspect of the disclosed subject matter, the pressure chamber may be configured to increase in cross-section when pressurized such that greater forces are generated on the end seal due to the increased surface area. The pressure chamber may be configured to expand upon pressurization, yet maintain sufficient hoop strength at the distal section to maintain a constrained stent. In this embodiment, the outer tubular member may be constructed of a suitable material or composite of materials to allow expansion of the outer tubular member as the pressure chamber is pressurized.

The seals 152, 162, 252, 262, 352, 362 and guidewire seal (if provided) may each be formed as separate components and attached to a corresponding tubular component, or may be formed as part of a tubular component. The seal can be formed from any suitable material. For illustration purposes only, the seals may be rubber or silicon. In other embodiments, the seal may be formed from a low durometer rubber having a compressed state and an expanded state. In the initial delivery configuration, the seal can be significantly crushed and deformed, transitioning to an expanded state when the pressure chamber is pressurized. Alternatively, the seal may be made of a hydrophilic polymer that absorbs fluid in the pressure chamber and expands with the outer tubular member.

For illustrative purposes only, hydrophilic materials such as, but not limited to, HydroMed™, Hydrothane™, Hydak ^(R) may be used for the seal. Seals constructed from such materials can be configured to swell when exposed to an aqueous environment, thereby sealing more tightly while maintaining lubricity. The seal may comprise a material or composite of materials that expands accordingly to match the size of the outer tubular member. That is, the seal expands with the outer tubular member to maintain a sufficient seal. As the pressure chamber expands, the exposed surface area of the seal also increases, resulting in a proportional increase in the retraction force for a given fluid pressure. Thus, the expanded pressure chamber provides greater retraction force for a given pressure. Alternatively, the seal may be constructed of a hydrophobic material for use with a suitable pressurized fluid. For example purposes only, a silicone seal with Hydromer 2314-172 coating may be used. Additionally or alternatively, high viscosity hydraulic fluid may be used to further impede leakage across the seal. In another embodiment, an O-ring may be used in a sealing configuration constructed of silicone, buna, or other suitable elastomer. Also, for purposes of example, but not limitation, the seal may comprise a hose, such as a low durometer Pebax.

Similarly, the liner may be constructed of any suitable material including, but not limited to, PEEK, Pebax, polyethylene, HDPE, a blend of HDPE and LDPE, a blend of nylon L75/L25, and the like. Additionally, the liner may comprise a combination of metallic material, low density polyethylene, silicon, nitrile, soft Pebax 30, or other blends of suitable materials, and may be coated with a suitable material as known in the art. According to another aspect of the disclosed subject matter, a spacer element or O-ring (not shown) may be provided within the pressure chamber. The spacer element can prevent the outer tubular member and seal from collapsing during delivery and storage of the catheter. The spacer element may also reduce the amount of fluid required to retract the outer tubular member. The spacer elements may be made of any of a variety of suitable shapes and materials, such as ring members having diameters that fit within the inner and outer diameters of the inner and outer tubular members, respectively. Alternatively, the proximal and distal seals may be coated with a hydrophobic layer such as, for example, oil or wax, or the seals may be made of a hydrophobic material such as a fluorocarbon or an olefin like polypropylene or suitable for use with a pressurized fluid. other hydrophobic materials used.

According to another aspect of the disclosed subject matter, and as embodied herein in FIGS. For the delivery of medical devices. For example, catheter 100 may include an endovascular prosthesis, such as stent 2 , positioned on stent mount 3 such that stent 2 is positioned between inner tubular member 110 and outer member 120 at the distal end of catheter 100 . In the first position, the outer member 120 holds the stent 2 in a compressed or delivery state. As discussed further above and below, the stent 2 is allowed to expand to the second position as shown in Figures 4-6 as the outer member 120 is retracted by the pressure chambers working in series. Movement of the outer member or sheath 120 in the proximal direction P exposes the self-expanding stent 2 .

If desired, a bumper or stopper component may be positioned proximally relative to the stent 2 to act as a stent seat. For example, and as provided in FIG. 5 , according to another aspect of the disclosed subject matter, catheter 100 may include stopper 31 secured to inner tubular member 110 . Stopper 31 may be formed as first distal stopper 161 as shown in FIGS. 4A-4D or may be configured to be distal relative to first distal stopper 161 and relative to the medical device to be delivered. (eg stent 2) is proximal. While the guidewire lumen and guidewire are omitted for clarity in FIGS. 4A-D for purposes of demonstrating fluid flow within the chamber, it should be appreciated that stopper 31 includes a guidewire lumen extending therethrough. Stopper 31 may be made of or include a radiopaque material. Radiopacity can provide enhanced visibility for proper catheter placement at the treatment site. Thus, the stopper 31 may be a radiopaque marker. For example, the marker may be a radiopaque metal ring or constructed of a tungsten-loaded polymer for increased softness and flexibility. Other suitable markers known may be used.

According to an embodiment of the disclosed subject matter, there is provided a method of deploying a catheter as previously described. In the embodiment of FIGS. 4A-4D , pressurized fluid is introduced into fluid lumen 130 through an adapter (not shown). As the fluid is introduced, the fluid enters the first and second pressure chambers C1 and C2 generally in series via the first distal flow port 421 and the second distal flow port 422 , respectively. When the appropriate volume of fluid has entered both pressure chambers, pressure chambers C1 and C2 are pressurized and internal forces develop therein. Pressure chambers C1 and C2 cooperate together to drive the outer tubular member in the proximal direction P.

The following description within the pressure chambers C1 , C2 provides an example of the co-operation of the pressure chambers C1 , C2 with an expansion space X1 initially defined therebetween to drive the outer tubular member in the proximal direction P. Other suitable operations are also contemplated.

As depicted in FIG. 4A , first proximal seal 152 and first distal seal 162 seal fluid within first pressure chamber C1 as fluid is introduced into first pressure chamber C1 . Once the amount of fluid entering the first pressure chamber C1 exceeds the initial volume of the first pressure chamber C1, the first pressure chamber C1 is pressurized, and an internal force is gradually built up within the chamber C1. Since the stopper 31 (acting in this embodiment as the first distal stopper 161) is fixed to the outer surface 111 and cannot move relative to the inner tubular part, the internal force is against the first distal stopper relative to the inner tubular part. The proximal stop 151 drives the first proximal seal 152 in the proximal direction P. As shown in FIG. Next, the relatively movable first proximal stopper 151 is driven in the proximal direction P, and thus the outer tubular part 120 is driven in the proximal direction P.

Simultaneously, as depicted in Figures 4A and 4B, fluid enters each pressure chamber in series. Thus, the above operations in the first pressure chamber C1 similarly take place in the second pressure chamber C2. For example, as fluid enters the first pressure chamber C1, fluid enters the second pressure chamber C2 in series. As fluid enters the second pressure chamber C2, the second proximal seal 252 and the second distal seal 262 seal the fluid within the second pressure chamber C2. Once the amount of fluid entering the second pressure chamber C2 exceeds the initial volume of the second pressure chamber C2, the second pressure chamber C2 is pressurized, and an internal force builds up within the chamber C2. As presented herein for purposes of illustration, since both the second pressure chamber C2 and the first pressure chamber C1 receive fluid from the same fluid lumen 130, and both chambers have substantially similar dimensions, chambers C1 and C2 will reach their maximum initial volume at about the same time. If one of the pressure chambers reaches its maximum initial volume before the other pressure chamber(s), fluid entering the fluid lumen generally equalizes the pressure in the other chambers.

Similarly, internal forces cause second proximal seal 252 to engage against second proximal stop 251 because second distal stop 261 is fixed to outer surface 111 and is immovable. Next, the movable second proximal stopper 251 moves in the proximal direction P in series with the first proximal stopper 151 movable in the proximal direction P. As shown in FIG. As the second proximal stop 251 moves in series with the first proximal stop 151 , the outer tubular member 120 attached to the second proximal stop 251 and the first proximal stop 151 likewise Move in the proximal direction P. The first proximal stopper 151 is movable relative to the inner tubular member 110 to a proximal position relative to the second distal flow port 422 to expose the first pressure chamber C1 to the second distal flow port 422 .

If for example purposes a third pressure chamber C3 is provided as embodied in Figure 5, the fluid enters each pressure chamber in series, and the operation as described above within the first and second pressure chambers C1 and C2 The same takes place in the third pressure chamber C3. Thus, as fluid enters the second pressure chamber C2 and the first pressure chamber C1, fluid enters the third pressure chamber C3 in series. As fluid enters third pressure chamber C3, third proximal seal 352 and third distal seal 362 seal fluid within third pressure chamber C3. Once the amount of fluid entering the third pressure chamber C3 exceeds the initial volume of the third pressure chamber C3, the third pressure chamber C3 is pressurized, and an internal force is gradually built up in the chamber C3. Since all three pressure chambers C1 , C2 and C3 can receive fluid from the same fluid lumen 130 , all chambers C1 , C2 and C3 will be closed before the internal forces within each chamber, respectively, are sufficient to move the outer tubular member 120 in the proximal direction P. Completely filled with fluid and then pressurized. For example, if the third pressure chamber C3 and/or the second pressure chamber C2 are filled before the first pressure chamber C1 , fluid entering the fluid lumen will continue into the first pressure chamber C1 for a balanced pressure within the chambers.

The internal force causes third proximal seal assembly 350 to engage third proximal stop 351 . Next, the movable third proximal stop 351 is driven in the proximal direction P in conjunction with the proximal stop 251 and the first proximal stop 151 . As the third proximal stop 351 moves in series with the second proximal stop 251 and the first proximal stop 251 , the outer tubular member 120 attached to all three stops similarly moves along the proximal stop 251 . The lateral direction P is driven.

Like the first expansion space X1, the second expansion space X2 will decrease in volume as the second proximal seal assembly 250 moves proximally and the second pressure chamber C2 increases in volume.

As the outer tubular member 120 continues to be driven in the proximal direction P, when the first proximal seal assembly 150 engages the second distal seal assembly 260, the first pressure chamber C1 will merge with the first expansion space X1 and eventually nothing but The first distal flow port 421 is also exposed to the second distal flow port 422 . Similarly, when the second proximal seal assembly 250 is engaged with the third distal seal assembly 360 , the second pressure chamber C2 can merge with the second inflation volume X2 and, ultimately, also be exposed to the third distal flow port 423 . In operation, the retraction force generated by the catheter of the disclosed subject matter will be a function of the number of pressurized chambers. For example, each chamber will generally provide a retraction force F as determined by the pressure within the chamber and the effective surface area at the corresponding seal assembly. Thus, for the catheter of Figure 4A with two pressure chambers, the resultant force will initially be approximately 2xF. As shown in FIG. 4C , when the first pressure chamber C1 merges with the first expansion volume X1 and is eventually exposed to the second distal flow port 422 , the retraction force will thus be reduced to 1×F.

Thus, the timing of reducing the retraction force can be selected or customized as desired. For example, where the second distal flow port is positioned adjacent to the second distal seal assembly, and the first inflation space has an initial length d1, when the outer tubular member has been retracted a distance of approximately d1, the The resultant force of the embodied catheter will be reduced from about 2xF to about 1xF. As shown in Figure 7, the distance dl can be matched to the retraction distance required to overcome the initial deployment force.

Similarly, as shown in Figure 5, if three chambers are provided, the initial resultant force will be approximately 3xF. When the first pressure chamber C1 merges with the first expansion space X1 and is finally exposed to the second distal flow port 422, the force will decrease to about 2×F, and, when the first pressure chamber X1 is further integrated with the second expansion space When X2 is fused and exposed to the third distal flow port 423, this force will be reduced to about 1×F.

The timing of the fusion of the first pressure chamber C1 with the first expansion space X1 and the timing of the fusion of the second pressure chamber C2 with the second expansion space X2 may be configured to occur simultaneously or at different times during retraction, and, thereby, at predetermined occurs at the location. As mentioned above, the timing at which each fusion occurs will depend on the distance of each expansion space and the location of the corresponding flow ports. Accordingly, the first and second expansion spaces may have different overall lengths for staggered fusion timing. In one embodiment, the closest pressure chamber is the longest pressure chamber of the catheter.

In another embodiment, the pressure chambers C1 , C2 and C3 and the expansion spaces X1 , X2 respectively have similar sizes for the pressure chambers to merge in adjacent expansion spaces at about the same time. As evidenced in FIGS. 4A-4D , retraction of the outer tubular member 120 results in exposure of the stent seat 3 and release of the stent 2 from the inner tubular member 110 . Fluid from the pressure chamber can then optionally be drawn off. If necessary, negative pressure can be drawn in the chamber to lock the outer tubular member in place. The catheter 100 can then be removed from the vasculature while the stent 2 remains released.

Operation of the catheter is also controlled by a suitable pressurizer (not shown) capable of maintaining a selected pressure. For example, when driving the outer tubular member in the proximal direction, the pressurizer may control the pressure increase in the chamber to ensure that the outer tubular member is not driven in the proximal direction too abruptly. The pressurizer controls movement of the outer tubular member in a proximal direction. Also, a locking mechanism may be provided to maintain a selected pressure or provide only a predetermined volume of fluid to prevent continued retraction.

The number of pressure chambers provided for the catheter and the relative lengths of the pressure chambers and expansion spaces can be selected or determined based on the length of the stent or device to be deployed. For example, without limitation, a catheter with two pressure chambers may be provided for stents ranging between approximately 60mm and 80mm. In another embodiment, a catheter with three pressure chambers can be adapted for stents over 80 mm.

In embodiments of the disclosed subject matter, the inner and/or outer tubular members may also be manufactured using various known techniques such as, but not limited to: extrusion, injection molding, blowing, drawing, deep drawing , polymerization, crosslinking, impregnation from solution, powder deposition, sintering, electrospinning, melt spinning, deformation at temperature, stretch blowing, chemical grafting, any combination of the above with reinforcing elements such as metal Braids, coils, glass fibers, carbon fibers and other kinds of organic or inorganic fibers, liquid crystals, and traditional processing techniques like hot-melt laser welding, milling, drilling, grinding, etc. Where metal components such as hypotubes are involved, various metal fabrication techniques may be used, such as but not limited to machining, tube drawing processes, drilling, milling, EDM, other deformation methods, electroplating, sputtering, electrografting , sintering and deposition e polishing. In one embodiment of the disclosed subject matter, the inner tubular member comprises a stainless steel hypotube at least at its proximal end.

The outer member may be formed from any suitable material or composite that allows expansion. This includes semi-compliant materials and materials that expand when the outer member is inflated and/or the pressure chamber is pressurized and retract when the chamber is depressurized and the outer member is deflated. The outer part can be single layer, double layer or multilayer and can be further reinforced. For example and without limitation, the outer member may be a multi-layered tube or balloon comprising flexible and rigid layers having a frangible structure configured to rupture upon inflation. The rigid layer can constrain and axially lock the medical device during shipping, storage and delivery, but can rupture upon initial pressurization of the pressure chamber. Once the rigid layer breaks, the flexible layer can maintain a seal while substantially increasing the diameter across the pressure chamber.

Additionally or alternatively, the outer component may have a rigid inner layer and a flexible outer layer, wherein the rigid layer is composed of a material that is soluble by the selected fluid medium. A fluid medium may be utilized to pressurize the pressure chamber, thereby dissolving the rigid structure and thus releasing the axial lock and allowing the flexible outer layer to expand in diameter. The outer member may also be formed from a suitable shape memory material configured to expand across the pressure chamber when the chamber is filled with fluid. As a further alternative, the outer component may have a bistable design that transitions from a locked or collapsed configuration during delivery to an unlocked or expanded configuration upon an increase in fluid pressure in the pressure chamber.

The outer part may also have an inner layer attached to or formed with the outer layer. The inner layer or liner may include a lubricious material to facilitate sliding of the outer member in the proximal direction when the outer member is retracted. For example, different types of polymers such as PTFE or high density polyethylene (HDPE) can be used for the inner layer. Additionally, other lubricious polymers may be used. As embodied herein, the outer layer provides sufficient strength to receive the endovascular prosthesis therein, yet allows movement in the proximal direction P. Multiple layers may be formed separately and adhered or bonded together or coextruded as a single part.

In further accordance with the disclosed subject matter, the exterior component can include a reinforcement layer. For purposes of illustration only, a reinforcing layer may be disposed at a distal portion corresponding to the location of the stent seat, and disposed between the outer and inner layers, such as a braided or coiled material. For example, the reinforcement layer may be provided in the form of a braided stainless steel tube or sheet or the like. A braid may comprise flat filaments as opposed to having filaments with a circular cross-section. Alternatively, the reinforcement may be in the form of a tube comprising a fabric or suitably oriented filaments such as carbon fibers encased in a polymer matrix. Likewise, such reinforcing fibers may additionally or alternatively be incorporated into the inner and/or outer layers during the manufacturing process.

In embodiments where the outer component includes an inner layer, an outer layer, and a reinforcement layer, the outer component may be formed, by way of example, at least in the following manner. First, the inner layer is formed by a tubular extrusion process and is arranged around a forming mandrel. As embodied herein, the forming mandrel has a shape corresponding to the desired shape of the inner side of the outer component. Next, a reinforcement layer, which may be provided in the form of a stainless steel braid material, is positioned throughout the predetermined length of the inner layer. Next, the outer layer is extruded and positioned over the reinforcement layer. The outer layer may be provided throughout the reinforcement layer in the form of two separate tubular parts slightly overlapping at the ends. Various parts of the outer layer may be selected to provide different materials of different durometers as described above. The two portions of the outer layer may overlap an amount such as, but not limited to, about 0.1 inches. Next, a sleeve of heat shrinkable material is positioned throughout the entire exterior component assembly. Finally, heat is applied to the assembly. When heat is applied, the heat-shrinkable tubing shrinks and causes the inner and outer layers to fuse, trapping the reinforcement layer therebetween. The heating process also conforms the inner layer to the shape of the forming mandrel. After the assembly cools, the heat shrinkable tube is cut off, leaving the outer part.

As a further alternative, the inner tubular part and/or the outer part may be constructed from a plurality of outer tubes. One or more proximal stops may also form a joint for two adjacent outer tubes. The exterior component may also be constructed from a composite (such as a co-extrusion of different polymers) or a fiber-reinforced composite (such as a fiber-reinforced resin material or braided material) comprising articles of multiple different materials. For purposes of illustration only, additional embodiments may include a braided tube with a PTFE liner, a polyimide middle layer with a braid, and a Pebax 72D outer layer. Additionally, to improve flexibility, helical or helical component configurations can be used in the configuration of the inner and outer components.

Each of the inner and outer tubular members may be of one-piece construction or assembly of members, and may be constructed of any suitable material. For example, suitable materials include, but are not limited to, polymeric materials such as nylon, urethane, polyurethane, PEEK, PTFE, PVDF, Kynar, PE, HDPE, three-layer materials including L25, Plexar, PEBAX, or Polyethylene of various suitable densities. Also, at least a portion of the inner tubular member and/or the outer tubular member may be constructed from an alloy or metallic material, such as a stainless steel hypodermic tube. Example constructions for inner and/or outer tubular members include: single layer of PEEK; three layer materials of L25, Plexar, HDPE; or braided tube with PTFE liner, polyimide interlayer with braid, and Pebax 72D outer layer.

It is also contemplated that the inner tubular member may be constructed from other biocompatible materials. Accordingly, the inner tubular member of the catheter may be constructed from the polymers identified above, combinations or blends of such polymers (whether alone or in combination with other materials), or other bioabsorbable materials. For example purposes only, the inner tubular member may also be reinforced by adding reinforcement members such as wire coils. In one embodiment, the inner tubular member is reinforced by adding reinforcement members along a length corresponding to the pressure chamber, as further described herein.

The inner tubular member and/or outer tubular member may also be coated with any of a variety of materials and techniques to enhance performance, including proprietary materials owned by Abbott Laboratories (such as U.S. Patent No. 6,541,116, U.S. Patent No. 6,541,116, U.S. Patent No. No. 6,287,285 and US Patent No. 6,541,116, the entirety of which is hereby incorporated by reference) for various suitable coatings and coating techniques. For example, possible coating materials include lubricious materials such as Teflon® and hydrophobic materials such as silicone lubricant dispersion PN 4097 or hydrophilic materials such as hydrogels, or lubricious coatings.

While circular cross-sections are generally preferred, the inner and/or outer tubular members may have any suitable cross-sectional shape, including oval, polygonal or prismatic. The inner tubular member and/or outer tubular member may also be of any suitable size and diameter depending on the desired application. The catheter is suitably sized and configured for delivery within a corresponding body lumen for the intended indication, such as the vasculature for vascular intervention.

Additionally, the inner tubular member and/or outer can be constructed from PE, polypropylene, Kynar, or urethane by an extrusion process using an extruder such as can be obtained from any of a number of known suppliers. Tubular parts. The material can be post-processed in a variety of ways including, for example and without limitation, extrusion, molding such as by injection or dipping, textile processing such as weaving or weaving, and shaping. Rolling and welding of sheets of material, or vacuum forming into tubular shapes, may be suitable forming processes, to name a few examples.

According to another aspect of the disclosed subject matter, the retainer may be co-extruded or formed with corresponding inner and outer tubular members, or may be formed separately and bonded or otherwise joined to the tubular members. The stopper can be constructed from any suitable material including, but not limited to, PEEK, Pebax, Kynar, and the like.

Although the disclosed subject matter is described herein in terms of certain preferred embodiments, those skilled in the art will recognize that various changes and improvements can be made to the disclosed subject matter without departing from its scope. Additional features known in the art may also be incorporated, such as disclosed in US Patent No. 7,799,065 to Pappas, which is incorporated herein by reference in its entirety. Furthermore, while individual features of one embodiment of the disclosed subject matter may be discussed herein, or shown in the drawings of one embodiment and not in others, it should be apparent that an implementation Individual features of an example may be combined with one or more features of another embodiment or features from multiple embodiments.

Besides the various embodiments depicted and claimed, the disclosed subject matter also relates to other embodiments having the dependent features claimed hereinafter and any other possible combination of those features disclosed above. Moreover, additional features and aspects developed for single-chamber actuators may be used in conjunction with those disclosed herein (such as in the document entitled "Conduit with Hydraulic Actuator" and filed herewith and by the assignee of the archives disclosed in a commonly owned co-pending application) tandem chamber catheter combination. Therefore, within the scope of the disclosed subject matter, the specific features set out in the dependent claims and disclosed above may be combined with each other in other ways, so that the disclosed subject matter is to be understood as also specifically relating to any other Other examples of possible combinations. Also, while reference is made to stents throughout this disclosure, other suitable devices and implants can equally be delivered using the catheters and systems disclosed herein. Thus, the foregoing descriptions of specific embodiments of the disclosed subject matter are presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosed subject matter to those disclosed embodiments.

Many modifications, changes, or other equivalents to the specific embodiments described above will be apparent to those skilled in the art. The scope of the disclosed subject matter is intended to be defined by the following claims and those modifications, changes and equivalents which will be apparent to those skilled in the art.

Claims (33)

1. a conduit, comprising:

Inner tubular member, it has length, outer surface and is defined in fluid tube chamber wherein, described outer surface limit the first distally flowing ports being communicated with described fluid tube chamber fluid and be communicated with described fluid tube chamber fluid be positioned to the second distally flowing ports in nearside with respect to described the first distally flowing ports;

Outer tubular element, it can move with respect to described inner tubular member along proximal direction along the length of described inner tubular member, and described outer tubular element has the inner surface towards the outer surface of described inner tubular member;

The first pressure chamber, it is defined between the outer surface of described inner tubular member and the inner surface of described outer tubular element, and, being defined between the first distally black box and the first nearside black box, described the first pressure chamber is communicated with described the first distally flowing ports fluid; With

The second pressure chamber, it is defined between the outer surface of described inner tubular member and the inner surface of described outer tubular element, and, be defined between the second distally black box and the second nearside black box, described the second pressure chamber is configured to be communicated with in nearside and with described the second distally flowing ports fluid with respect to described the first pressure chamber;

Wherein, the fluid of introducing by described fluid tube chamber makes described the first pressure chamber and described the second pressurisation of pressure chambers, to generate the corresponding power at described the first nearside black box and described the second nearside black box place, to drive described outer tubular element along proximal direction.

2. conduit according to claim 1, it is characterized in that, described the first distally black box comprises the first distal stopper and the first distal seal, the inner surface of described the first distal stopper from the outer surface of described inner tubular member to external component extends, and, be configured to respect to described the first distal seal in distally, to hinder described the first distal seal along the movement of distal direction, and further, wherein, described the first nearside black box comprises the first proximal stopper and the first proximal seal, described the first proximal stopper is extended from the inner surface of described outer tubular element, and, be configured to respect to described the first proximal seal in nearside, described the first proximal stopper can move with respect to described inner tubular member along proximal direction.

3. conduit according to claim 2, is characterized in that, at least one in described the first distally black box or described the second distally black box also comprises lining.

4. conduit according to claim 2, it is characterized in that, described the second distally black box comprises the second distal stopper and the second distal seal, described the second distal stopper is extended from the outer surface of described inner tubular member, and, be configured to respect to described the second distal seal in distally, to hinder described the second distal seal along the movement of distal direction, and further, wherein, described the second nearside black box comprises the second proximal stopper and the second proximal seal, described the second proximal stopper is extended from the inner surface of described outer tubular element, and, be configured to respect to described the second proximal seal in nearside, described the second proximal stopper can move with respect to described inner tubular member along proximal direction.

5. conduit according to claim 4, it is characterized in that, when making respectively described the first pressure chamber and described the second pressurisation of pressure chambers, described the first proximal seal engages described the first proximal stopper, and, described the second proximal seal engages described the second proximal stopper, to drive described outer tubular element along proximal direction.

6. conduit according to claim 4, it is characterized in that, described the first proximal stopper can move to respect to described the second position of distally flowing ports in nearside with respect to described inner tubular member, so that described the first pressure chamber is exposed to described the second distally flowing ports.

7. conduit according to claim 1, it is characterized in that, the outer surface of described inner tubular member also limits the 3rd distally flowing ports, described the 3rd distally flowing ports is with respect to described the second distally flowing ports in nearside, and described the 3rd distally flowing ports is communicated with described fluid tube chamber fluid, and wherein, described conduit also comprises the 3rd pressure chamber being communicated with the 3rd distally flowing ports fluid of described fluid tube chamber, described the 3rd pressure chamber is defined in the outer surface of described inner tubular member, the inner surface of described outer tubular element, between the 3rd nearside black box and the 3rd distally black box, wherein, the fluid of introducing by described fluid tube chamber makes described the 3rd pressurisation of pressure chambers of connecting with described the first pressure chamber and described the second pressure chamber, power is put on to described the 3rd nearside black box, to drive described outer tubular element along proximal direction.

8. conduit according to claim 7, it is characterized in that, described the 3rd distally black box comprises the 3rd distal stopper and the 3rd distal seal, described the 3rd distal stopper is extended from the outer surface of described inner tubular member, and, be configured to respect to described the 3rd distal seal in distally, to hinder described the 3rd distal seal along the movement of distal direction, and further, wherein, described the 3rd nearside black box comprises the 3rd proximal stopper and the 3rd proximal seal, described the 3rd proximal stopper is extended from the inner surface of described outer tubular element, and, be configured to respect to described the 3rd proximal seal in nearside, described the 3rd proximal stopper can move with respect to described inner tubular member along proximal direction.

9. conduit according to claim 1, is characterized in that, described inner tubular member also has the guidewire lumen being defined in wherein.

10. conduit according to claim 9, is characterized in that, described guidewire lumen has the proximal guidewire port that the near-end with respect to described conduit separates in distally.

11. conduits according to claim 9, is characterized in that, also comprise and are disposed at described fluid hose intracavity to limit the wire leading pipe of described guidewire lumen.

12. conduits according to claim 9, it is characterized in that, described guidewire lumen is defined in described fluid tube chamber, described inner tubular member also comprises proximal guidewire sealing member and distal guide sealing member, described proximal guidewire sealing member and distal guide sealing member are disposed in described fluid tube chamber, with engagement arrangement hermetically in the intraluminal seal wire of described fluid.

13. conduits according to claim 12, is characterized in that, at least one in water wetted material, hydrophobic material or molding water wetted material of at least one in described proximal guidewire sealing member or described distal guide sealing member forms.

14. conduits according to claim 3, it is characterized in that, at least one in water wetted material, hydrophobic material or molding water wetted material of at least one in described the first distal seal, described the first proximal seal, described the second distal seal or described the second proximal seal forms.

15. conduits according to claim 1, is characterized in that, also comprise the radiopaque marker that is fixed on described inner tubular member.

16. conduits according to claim 15, is characterized in that, described radiopaque marker sealing is the described fluid tube chamber in distally with respect to described the first distally flowing ports.

17. conduits according to claim 1, is characterized in that, also comprise reinforcement feature, and described reinforcement feature connects along at least one corresponding part described inner tubular member and in described the first pressure chamber or described the second pressure chamber.

18. conduits according to claim 1, is characterized in that, also comprise the carrier base along described inner tubular member configuration in distally and the support that is positioned described carrier base place with respect to described the first pressure chamber.

19. conduits according to claim 18, is characterized in that, described outer tubular element is extended jointly in primary importance and described carrier base, and, make described outer tubular element move to the second position along proximal direction, to launch described support.

20. conduits according to claim 1, is characterized in that, described outer tubular element is formed by shape-memory material, and epitheca can radially expand after the fluid temperature (F.T.) increase in described pressure chamber.

21. conduits according to claim 1, is characterized in that, described outer tubular element comprises multi-ply construction.

22. conduits according to claim 1, it is characterized in that, also comprise the first expansion space, described the first expansion space is defined between the outer surface of described inner tubular member and the inner surface of described outer tubular element, and, be defined between described the first pressure chamber and described the second pressure chamber, described the first expansion space is configured to along with described the first pressure chamber increases volume and reduces volume.

23. conduits according to claim 22, is characterized in that, described the first expansion space is initially filled with compressible fluid.

24. conduits according to claim 22, is characterized in that, when described outer tubular element moves predetermined distance along proximal direction, merge described the first pressure chamber and described the first expansion space.

25. conduits according to claim 23, is characterized in that, when described outer tubular element moves described predetermined distance along proximal direction, described the first pressure chamber is exposed to described the second distally flowing ports.

26. conduits according to claim 23, is characterized in that, described the first pressure chamber generates lasting retraction, to drive described outer tubular element to surpass described predetermined distance along proximal direction.

27. conduits according to claim 1, is characterized in that, described the first pressure chamber and described the second pressure chamber jointly generate initial retraction makes a concerted effort, initially to drive described outer tubular element along proximal direction.

28. conduits according to claim 7, is characterized in that, also comprise the first expansion space between described the first pressure chamber and described the second pressure chamber and be positioned described the second pressure chamber and described the 3rd pressure chamber between the second expansion space.

29. conduits according to claim 4, is characterized in that, described the first nearside black box is moved into respect to described the second distal stopper in nearside, so that described the first pressure chamber is exposed to described the second distally flowing ports along proximal direction.

30. conduits according to claim 4, is characterized in that, described the second distal stopper is formed at least in part by bulge, platform, sleeve, elevated portion or step.

31. conduits according to claim 30, is characterized in that, described bulge has wedge shape or conical configuration.

32. conduits according to claim 1, is characterized in that, also comprise prelum, and described prelum is communicated with for the intraluminal fluid of described fluid.

33. 1 kinds of methods of launching conduit, comprising:

Conduit is provided, and described conduit comprises:

Inner tubular member, it has length, outer surface and is defined in fluid tube chamber wherein, described outer surface limit the first distally flowing ports being communicated with described fluid tube chamber fluid and be communicated with described fluid tube chamber fluid be positioned to the second distally flowing ports in nearside with respect to described the first distally flowing ports

Outer tubular element, it can move with respect to described inner tubular member along proximal direction along the length of described inner tubular member, and described outer tubular element has the inner surface towards the outer surface of described inner tubular member,

The first pressure chamber, it is defined between the outer surface of described inner tubular member and the inner surface of described outer tubular element, and, be defined between the first distally black box and the first nearside black box, described the first pressure chamber is communicated with described the first distally flowing ports fluid, and

The second pressure chamber, it is defined between the outer surface of described inner tubular member and the inner surface of described outer tubular element, and, be defined between the second distally black box and the second nearside black box, described the second pressure chamber is configured to be communicated with in nearside and with described the second distally flowing ports fluid with respect to described the first pressure chamber;

Device is configured between the outer surface of described inner tubular member and the inner surface of described outer tubular element with respect to described the first position of distally black box in distally; And

Fluid is introduced in described fluid tube chamber, so that described the first pressure chamber and described the second pressurisation of pressure chambers, to generate the corresponding power at described the first nearside black box and described the second nearside black box place, to move described outer tubular element along proximal direction, so that described device exposes.